So are you saying after going through the wizard you clicked 'change settings' and landed on the Network Scan Settings page. From there did you click Edit on the scan range. Or did you add the account for esx through the accounts area further down on the page and then go back to the scan range to add the account? I'm not following the flow you went through.

I'm sure you are on to something. This is a new scan option and one of the reasons for the pre-release.

I think I figured out what you were experiencing. You were scanning using current user and so you did not enter credentials in the wizard. When you view the scan range on the network scan settings page you will see the windows account that was used. When you click Edit on the range, the wmi account is not selected in the dropdown. So if you then add your ESX info. at this point and do not touch the wmi settings, your Windows account will be cleared out. I will report this as a defect and cofirmed it existed in 4.5 too.